Hemming and crimping die



Jan. 1, 1963 1.. ASKINAZY HEMMING AND CRIMPING DIE 4 Sheets-Sheet 1 Filed Jan. 24, 1961 Fig.4

Leo As/rinazy INVENTOR. MM. BY -May all Jan. 1, 1963 L. ASKINAZY HEMMING AND CRIMPING DIE 4 Sheets-Sheet 2 Filed Jan. 24, 1961 Lea Ask/hazy INVENTOR.

1 BY W L. ASKINAZY HEMMING AND CRIMPING DIE Jan. 1, 1963 4 Sheets-Sheet 3 Filed Jan. 24, 1961 c Z/ 472/ w Leo Askinazy /56 IN VENTOR.

/0 BY WWW fiM Jan. 1, 1 963 L. ASKINAZY 3,071,176

HEMMING AND CRIMPING DIE Filed Jan. 24, 1961 4 Sheets-Sheet 4 Fig. a 9

Leo Askl'nazy INVENTOR.

BY W 3 atenr Patented .Ia'n. l,

3,071,176 HEMIVIING AND CRIMPING DIE Leo Aslrinazy, fviark Stamping Co., Inc. 458 'ihatford Ave, Brooklyn, N.Y. Filed Jan. 24, 1961, Ser. No. 84,541 13 (llaims. (Cl. 153-42) This invention relates to a device for bending sheet material, and more particularly to a machine for complating a hem or lap on a piece of sheet material in one cycle of reciprocating motion which consists only of one down and one up stroke.

It is another object of the invention to provide a machine for speeding up production of hemming of sheet material by providing a machine which will complete the hemming operation in one operation instead of two operations as done at present.

Another object of the invention is to provide a device for hemming sheet metal in one reciprocating action which is adapted to be used with any conventional press or press brake and to be driven by any conventional power source.

Yet another object of the invention is to provide a device for hemrning sheet metal which will more accurately and more quickly perform the bending operation than machines now in use.

Still another object of the invention is to provide a die for a press for bending sheet materials which will bend the material neater and more efficiently than conventional dies now in use.

Yet another object of the invention is to provide a die for a press or press brake which will reduce the manpower required to perform a given amount of work.

It is yet another object of the invention to provide a machine for bending sheet materials which is relatively simple in design, economical to manufacture and maintain, and durable and reliable in use.

It is still yet another object of the invention to provide a machine for bending the edges of sheet materials and having an adjustment thereon for varying the location of the bend as desired.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to be accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a perspective view of the invention looking downwardly upon the front right portion thereof;

FIGURE 2 is a top or plan view of the device shown in FIGURE 1;

FIGURE 3 is a rear view of the device shown in FIG- URE 1;

FIGURE 4- is a cross sectional view taken substantially on the plane of line 4-4 of FIGURE 2 but showing the location of the various parts of the machine at the very beginning of a cycle of operation;

FIGURE 5 is a cross sectional elevational view taken substantially on the plane of 5--'5 of FIGURE 2 and showing the male die' at the very bottom of its stroke;

FIGURE 6 is a view similar to FIGURE 4 but showing the male die returning to and approaching its original position;

FIGURE 7 is a perspective view showing a piece of sheet material that has been hemmed by the machine comprising my invention;

FIGURE 8 is an end view partially in section of my invention and illustrating a modified form of die used therewith;

FIGURE 9 is a perspective View of a sheet of material hemmed by the modified dies shown in FIGURE 8;

FIGURE 10 is a view similar to FIGURE 8 but showing a third form of die;

FIGURE 11 is a view similar to FIGURE 10 but showing the dies in the fully mated position; and

FIGURE 12 is a perspective view of a sheet of material hemmed by the form of dies shown in FIGURES l0 and 11.

Referring to the drawings, It represents the stationary framework of the press machine which supports the various operating parts thereof. Afiixed to the upper portion of the frame It} are two parallel head members 12 and 34 of substantially inverted L-shape.

Rotatably journaled in the head members 12 and 14 is a horizontally extending driveshaft 16 having two gears 13, 2 2 ailixed thereto at its right end and embracing each side of the head member 12. Fixed to the left end of the driveshaft 16 is a gear member 26 adjacent the inside face of the head 14.

Each of the head members 12 and 14 have a substantially rectangular recess 26 (FIGURE 5) formed in their inside faces and extending down to the lower edges of the heads. Extending between the two recesses 26 is a die plate 28 which is substantially rectangular in shape and has its ends extending into the recesses and vertically slidable therein. The bottom edge of the die plate is beveled to form a male die 29 and on each end of the plate 28 is integrally formed or secured thereto by conventional means, a vertically extending rack 30 having teeth mating and interengageable with the pinions 2d and 22.

Pivotally mounted on the right head member 12 is a shaft 34 having fixed thereto a T-handle 36 and a pinion 38 having teeth interengageable with the teeth of pinion 18.

Fixed to the back side of plate 28 are two pairs of arms 40, 42 which pivotally support on pins 44 identical dogs 46 and 48. The dogs are substantially triangular in shape and have upper legs 50 which are slightly longer than lower legs 52 and a cam surface 54 joining the ends of the two legs.

The upper surface of the frame It supports a die support plate 56. The support plate 56 extends across the entire width and depth of the frame and has an integrally formed rib 53 extending the entire length thereof and machine fitted within a corresponding groove 60 in the upper portion of the frame.

Fixed to the support plate 56 at its upper front portion is the fixed part of the female die 64. As shown in FIGURE 1, the fixed portion 62 of the female die is slightly shorter in length than the plate 56 and is centered thereon with its ends equally spaced from the ends of the plate 56. Mounted adjacent to and directly behind the fixed portion 62 is a mechanism or pivoted portion 66 of the female die. Fixed to or integrally formed with the ends of the member 66 are two arms 68, 70 which are mirror images of one another. As shown in FIGURE 1, each of the arms 68 and 70 has a forward portion 72 which overlaps the ends of the fixed female die member 64. The forward portions 72 have circular holes drilled therein which pivotally receive studs 74 which are threaded into and thereby fixed to the ends of fixed die members 62. Normally the arms 68 and 70 rest flat upon the plate 56 as shown in FIGURE 1, however, the studs 74 permit the arms 68 and 70 to rotate in a counterclockwise direction as viewed in FIGURE 1.

Affixed to the back of the pivoting female die member 66 are two pairs of roller support arms and 82. Each pair of support arms has a horizontal pin extending therebetween and rotatably supporting a roller 76 or 78.

As shown in FIGURES 2, 3 and 6, four parallel support arms 86, 88, and 92 are fixed to and extend upwardly from the back edge of the plate 56. Extending between each pair of support arms are horizontally extending pivot pins 94. Each pivot pin 94 pivotally sup ports an L-shapcd lever 96 or 98. Each of the levers 96 and 96 have an upper horizontally extending arm 1611 joined to a vertically extending arm 1112. The arms 100 and 1132 are joined together and reinforced at their sides by a plate 104.

Extending between each pair of plates 1% is a horizontal pin 166 substantially parallel to pin 94. Extending between each pair of reinforcing plates 104 and pivotaliy mounted on each of the pins 166 is a die operating plate 168 and threaded in the lower central portion of the arms 162 is an adjusting screw or stud 1111 for adjusting the normal position of plate 163 relative to arm 102.

As shown in FIGURES 2, 3 and 6, each pair of the support arms has one backstop 112 secured thereto. As shown in FIGURE 3, the arm 90 has the backstop 112 secured thereto by two bolts 114 and the arm 83 has the backstop 112 firmly secured thereto by the two bolts 114. Threaded into each backstop 112 is a backstop screw 116 having a lock nut 118 threaded thereon. By adjusting the screw 116, the position of arm 102 can be determined when it is rotated in a counterclockwise direction as far as it will go as shown in FIGURE 5.

Each of the upper arms 100 have their lower surfaces notched to receive a rectangular striker plate 120. The striker plate 120 is replaceable as it is secured to the arms by studs 122 and 124. The striker plate is preferably formed of some hard and wear-resisting material as tool steel.

The major portions of the arms 68 and 70 which are secured to the female die member 66 extend rearwardly of this die member, and the rear ends of the arms have apertures therein for receiving tension rod 126. The ends of the tension rod extend through these apertures and have threaded thereon nuts 123 and 136 which urge'the rear ends of the arms together. Threaded into the rear face of the female die member 66 are a plurality of horizontally extending and spaced studs 132 having semicylindrical recesses 134 therein which mate with the outer surfaces of the tension rod 126 as shown in FIGURE 5. The studs 132 are locked in final adjustment by locking nuts 136. By properly adjusting studs 132 and nuts 128, 1319, the curvature in the female die member can be eliminated. The number of studs 132 may be increased as necessary, depending upon the length of the die member. The tension rod 126 also acts as a structural brace for rigidifying the female die member.

While the press has been illustrated as being operative by a manual lever 35, it is obvious that the male die member 23 can also equally well be operated by conventional power means such as electrical motors, pneumatic devices, hydraulic motors, etc.

Mounted on top of the female die member 66 is a gauge plate 146 having parallel and spaced slots 142 extending vertically therethrough. The gauge plate is secured to the top of the female die member by means of threaded studs or nuts 144.

In operation, the die plate is normally in its uppermost position as shown in FIGURE 4. The gauge plate 140 is then adjusted in a horizontal direction, the desired distance from edge 148 of the female die. The gauge plate 141) is then locked in final position by screwing down studs 144. The position of gauge plate 14!) determines the width of the hem 156 as shown in FIGURE 7. The sheet material 46 to be hemmed is then placed horizontally upon the top of the female die and with its inner edge abutting the gauge plate 140. The handle 36 is then rotated manually in a direction to reciprocate die plate 28 downwardly by means of gears 18, 20, 22 and racks 30 and 31.

As the plate 23 moves downwardly, the dogs 48 contact the striker plates 12ft causing the dogs to rotate in a counterclockwise direction until the short legs 52 are substantially horizontal thereby permitting the dogs to pass below the striker plates. The L-shaped arms 96 and 98 are prevented from rotating in a counterclockwise direction by the backstops 112 and 112. As the male die member 29 moves downwardly it contacts the sheet 146 and forces it into the female die as shown in FIGURE 5 and forms a flange on the edge of the plate. The flange 35 thus formed makes an an le of approxi mately 45 degrees with the sheet 146. The sheet material 146 is held within the female die by friction after the male die 29 begins to move upwardly.

As shown in FIGURE 6, as the die plate 28 moves upwardly, the upper leg 50 of the dog 48 and the upper leg 50 of the dog 46 contact the lower surface of striker plate 120 at the outer edge thereof thereby rotating the L-shaped levers 98 and 96 in a clockwise direction about the pivot pin 94. The pivot pins 166 and the adjusting bolt 116 cause the die operating plates 1% to also rotate clockwise with the L-shaped arms about the pivot pin 94. As the plates 108 rotate in a clockwise direction about pins 94, they strike the rollers 76 and 78 which through their support arms 80 and 82 cause the pivoted female die member 66 to rotate in a counterclockwise direction about the studs 74. As the female die member rotates in a counterclockwise direction, it bends flange flat against plate 146 thereby forming hem 156. If the press 2 is properly adjusted, the tips 5'1 of the arms 50 will slip past the lower corner of plate 120 as shown in FIGURE 6 when flange 35 is pressed flat against the plate or sheet 146. Once the dogs 51) move past the plate 120, gravity will force the arms 68 and 70 back to their original hori- 39 zontal position shown in FIGURE 4. Since the rollers 76 and 78 contact plates 108, which in turn contact adjusting studs 110, the L-shaped levers 96 and 98 are also forced back to their original position as shown in FIG- URE 4.

As shown in FIGURE 5, the dogs 48 and 46 cannot rotate in a clockwise direction about pin 44 because the short legs.52 are abutting against the surfaces 53 which are fixed to plate 28.

Proper adjustment of the operating mechanism is accomplished by means of studs 116 and backstop adjusting screws 116. By proper adjustment of the studs 116 and backstop adjusting screws 116, any bend of plate 146 from zero to any desired bend up to a complete hem as shown at 150 in FIGURE 6, can be obtained.

In the modification shown in FIGURE 8, the male die member 29 has a rectangular groove 166 formed in its lower rear portion. The groove 166 is filled by replaceable die tool 162 which is substantially rectangular in cross section and has a rounded or circular lower edge 164. The tool 162 may be retained on the die member 29 by conventional means such as bolts or tack welds, not shown.

The female die member 62' has a sloping surface 67 whose lower end is slightly curved as illustrated at 166. The pivoted portion 66' of the female die member has a rectangular recess 168 formed therein on its upper front edge which is substantially filled by a removable die tool 170. The die tool 170 may also be retained in the die member 168 by conventional means such as screws or tack welds. The front surface of the die tool member 170 has an arcuate groove 172 extending longitudinally therein. The arcuate portions 166 and 172 merge and blend together to form an arcuate longitudinally extending groove at the bottom of the sloping portion 67' of the female die members. When the male die tool 162 is fully inserted into the female members 62 and 66 it forms an arcuate bend in the sheet 146. When the pivoted female die members 170 is pivoted against the surface 67', the sheet 146 is hemmed as shown in FIGURE 9. The hem 35' formed on the sheet is substantially tear-drop in cross sectlon.

FIGURES 10 and 11 illustrate a third form of my invention. In this form, a male die tool 162 is inserted into the slot 160. The die tool 162 has a plurality of spaced vertically extending bores 176 therein containing electromagnets 178. The lower ends of the electromagnets are grounded as indicated at 180 and the upper ends of the magnets connected by an insulated lead to a contact point 186 mounted in insulator 190. Pivoted above each contact 186 is an L-shaped switch member 182 composed of insulating material such as plastic. Switch member 182 is pivoted at 184 to the male die member 29" within a recess formed therein. Switch member 182 has a contact 183 connected by a conductor 189 to a source of electricity. As shown in FIGURE 10, the weight of switch member 182 causes it to pivot downwardly about the pivot point 184 so that the contact points 186 and 188 touch each other thereby energizing electroma-gnets 178. The lower portion of the die tool 162' has an arcuate recess 178 therein for receiving a rod 176 formed of magnetlic material. When the contacts 188, 186 energize electromagnets 178, the rod 176 is firmly held by magnetic force within the arcuate groove 174.

As shown in FIGURE 11, when the male die member 29" is forced downwardly into the arcuate recess 172, the rod 176 bends the sheet 146 as shown in FIGURE 11, and the switch element 182 contacts the upper surface of the die tool 1170 thereby pivoting the switch element about 184' for opening the switch 188, 186. When the switch is broken, the magnets 178 are deenergized thereby permitting the rod 176 to remain in the bend 171 of the sheet. When the die member 29" is withdrawn from the female die member, the die tool 176 bends the edge of the sheet 146" about the rod 176 as illustrated in FIG- URE 12. The hem 34 and flange 194 of the sheet 146" securely retains the rod 176 within the hem 35".

The hems 35 and 35" as illustrated in FIGURES 9 and 12 not only provide a smooth enlarged edge for the sheets 146' and 146 but also the rod 176 may function as a hinge, securing means, etc. for the sheet 146".

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention a claimed.

What is claimed as new is as follows:

l. A device for hemming a sheet of material between two mating die members comprising support means for supporting said die members, means for moving one of said die members on said support toward the other die member whereby a portion of said material is bent in one direction along a straight line, and means on said device for further bending said portion in said one direction along said straight line when said die members are moved apart, said other die being a female die composed of a plurality of parts hinged together on an axi parallel to said straight line, and the means for further bending said portion comprising mechanism pivoted directly on said support means, means on said one die for automatically engaging and disengaging the mechanism for rotating said mechanism when it moves in said one direction, connection means on one of said plurality of parts of said female die engaged by said mechanism for rotating said plurality of parts together whereby said portion is bent toward said sheet along said straight line for forming a hem on said sheet.

2. A device as defined in claim 1 wherein said means on said one die includes a dog, said dog being pivoted by striking said mechanism when said one die moves toward said other die so as to permit said one die to move freely past said mechanism, stop means on said one die preventing pivotal movement of said dog when said one die moves away from said other die.

3. A device as recited in claim 1 wherein said mechanism comprises an L-shaped lever pivoted directly on said support means and said connection means includes a roller journaled on said other die and operated by said L-shaped lever.

4. A device as recited in claim 2 wherein said dog comprises a short arm and a long arm substantially normal thereto.

5. A device as recited in claim 3 including a die operating plate pivoted at one end to said L-shaped arm, an adjusting screw between said plate and arm, the other end of said plate engaging said roller.

6. A device as recited in claim 5 including an adjustable back stop on said support for stopping said L-shaped lever.

7. A press comprising a two piece female die, each of said pieces being substantially elongated, means hinging said pieces in side-by-side relation, an open groove formed between said pieces, a male die movable into and out of said groove for forming material, and operating means between said male die and one of said female die pieces for pivoting said pieces together and closing said groove when said male die is moved out of said groove.

8. A device as recited in claim 7 wherein said operating means includes an automatic one-way drive whereby said one female die piece is operated only when the male die moves in one direction, the pivotal axis between the female die pieces being substantially coincidental with the bottom of the groove.

9. A device as defined in claim 7 wherein said groove is V-shaped, has side walls converging in a direction away from said male die and a semi-circular bottom and said male die has surfaces complementary to said converging side walls joined by a rounded edge thereby forming a tubular hem.

10. A press comprising a two piece female die, each of said pieces being substantially elongated, means hinging said pieces in side-by-side relation, an. open groove formed between said pieces, a male die movable into and out of said groove for forming material, and operating means between said male die and one of said female die pieces for pivoting said pieces together and closing said groove when said male die is moved out of said groove, said groove having downwardly converging side walls and a semi-circular bottom and said male die has surfaces complementary to said converging side walls, the male die side walls being joined by an arcuate groove, a circular magnetic rod in said arcuate groove, electromagnet means on said male die for holding said rod in said arcuate groove, and switch means connected to said electromagnet means operable to deenergize same when said male die is inserted into said open groove.

11. A hemming and crimping die assembly comprising a pair of dies movable toward and away from each other, one of said dies having a stationary section and a movable section cooperating to bend a sheet of material when the other die is moved toward said one die, said movable section being movable in a direction to continue the bend, an actuating mechanism for moving the movable section of said one die to continue the bend, means on said other die automatically engaging the actuating mechanism when the dies move toward each other and automatically disengaging from the actuating mechanism when the dies move substantially to their remote position.

12. The structure as defined in claim 11 wherein said stationary section and movable section define a groove therebetween for receiving the other die and the sheet material with the bottom of the groove defining a bend line, the path of movement of said movable section causing the movable section to continue the bend along the same line.

13. The structure as defined in claim 12 wherein said I actuating mechanism includes an angulated member having one leg engageable with the movable section, and pivotal latch means mounted on said other die for automatically engaging the angulated member during movement of the dies toward each other and actuating the actuating mechanism when the dies move apart, said latch means causing pivotal movement of the angulated member as the dies move apart and being automatically disengaged from the angulated member as the dies approach their remote position.

References ,Citefi in the He of this patent UNITED STATES PATENTS Nystrom Sept. 20, 1927 8 Franzen et a1. Mar. 6, 1934 Kenney et a1 Oct. 18, 1949 Robbins et a1 Ian. 28, 1958 FOREIGN PATENTS Germany Feb. 12, 1937 Germany Oct. 1, 1953 

1. A DEVICE FOR HEMMING A SHEET OF MATERIAL BETWEEN TWO MATING DIE MEMBERS COMPRISING SUPPORT MEANS FOR SUPPORTING SAID DIE MEMBERS, MEANS FOR MOVING ONE OF SAID DIE MEMBERS ON SAID SUPPORT TOWARD THE OTHER DIE MEMBER WHEREBY A PORTION OF SAID MATERIAL IS BENT IN ONE DIRECTION ALONG A STRAIGHT LINE, AND MEANS ON SAID DEVICE FOR FURTHER BENDING SAID PORTION IN SAID ONE DIRECTION ALONG SAID STRAIGHT LINE WHEN SAID DIE MEMBERS ARE MOVED APART, SAID OTHER DIE BEING A FEMALE DIE COMPOSED OF A PLURALITY OF PARTS HINGED TOGETHER ON AN AXIS PARALLEL TO SAID STRAIGHT LINE, AND THE MEANS FOR FURTHER BENDING SAID PORTION COMPRISING MECHANISM PIVOTED DIRECTLY ON SAID SUPPORT MEANS, MEANS ON SAID ONE DIE FOR AUTOMATICALLY ENGAGING AND DISENGAGING THE MECHANISM FOR ROTATING SAID MECHANISM WHEN IT MOVES IN SAID ONE DIRECTION, CONNECTION MEANS ON ONE OF SAID PLURALITY OF PARTS OF SAID FEMALE DIE ENGAGED BY SAID MECHANISM FOR ROTATING SAID PLURALITY OF PARTS TOGETHER WHEREBY SAID PORTION IS BENT TOWARD SAID SHEET ALONG SAID STRAIGHT LINE FOR FORMING A HEM ON SAID SHEET. 